Efinaconazole, (2R,3R)-2-(2,4-difluorophenyl)-3 -(4-methylenepiperidin-1-yl)-1-(1H-1,2,4-triazol-1-yl)butan-2-ol, also known as KP-103 and marketed under the trade name JUBLIA®' is effective against mycotic diseases in humans and animals represented by formula I:

U.S. Pat. No. 5,620,994 describe azolylamine derivatives and their use including Efinaconazole or pharmaceutically acceptable acid addition salts thereof, a pharmaceutical composition and a method of use.
The U.S. Pat. No. '994 also discloses a process for the preparation of Efinaconazole by reaction of (2R,3S)-2-(2,4-difluorophenyl)-3-methyl-2-[(1H-1,2,4-triazol-1-yl)methyl]oxirane (Formula 2) with 4-methylenepiperidine. In this method, the ring-opening addition reaction uses a large excess of 4-methylenepiperidine in water and involves prolonged heating under reflux.
U.S. Pat. No. 8,871,942 describes a process for the preparation of Efinaconazole. In this Efinaconazole obtained by reaction of (2R,3S)-2-(2,4-difluorophenyl)-3-methyl-2-[(1H-1,2,4-triazol-1-yl)methyl]oxirane (Formula 2) with acid addition salt of 4-methylenepiperidine.
There is always a need for alternative preparative routes, which for example, use reagents, solvents that are less expensive, and/or easier to handle, consume smaller amounts of reagents and solvents, provide a higher yield of product, involve fewer steps, have smaller and/or more eco-friendly waste products, and/or provide a product of higher purity.